1. Field of the Invention
The invention relates to a semiconductor device and a fabricating method thereof and more particularly relates to a resistive memory and a fabricating method thereof.
2. Description of Related Art
A resistive memory has the advantages of low operation voltage, fast operation speed, simplified structure, and good durability, etc. and thus has become the most potential memory type in recent years. Generally speaking, the operation modes for switching the storage state of the resistive memory include a unipolar switching and a bipolar switching. Specifically, the operation mode of the unipolar switching is to use voltage pulses of the same polarity (e.g. positive voltage pulse or negative voltage pulse) to perform a programming operation and an erasing operation of the memory cell. The operation mode of the bipolar switching is to use voltage pulses of different polarities to respectively perform the programming operation and the erasing operation of the memory cell.
In addition, for the conventional resistive memory, heat energy is generated due to the resistance characteristics of an electrode when an operation current passes through the electrode, and the heat energy changes the resistance state of the variable resistance material layer in the memory cell, thereby switching the memory state of the memory cell. However, the operation current heats the entire electrode, and the variable resistance material layer only contacts a part of the electrode. Thus, when sufficient heat energy is generated to change the resistance state of the variable resistance material layer, the heat energy generated at areas of the electrode that are not in contact with the variable resistance material layer is not used and wasted. Nevertheless, if the operation current is lowered to reduce waste of the energy, the operation efficiency of the device may decrease.